MARCH 14, 1940
Good visibility commends the layout of the Praga E.210
pusher for a light army co-operation machine.
For the observation of artillery fire up to, say, fifteen
miles behind the lines, a heavier and faster machine is
considered necessary. A French writer considers that this
might follow the layout of the Potez 63, a twin-engined
three-seater, fast and manoeuvrable, and armed with two
fixed and two free machine guns.
France is certainly using her Potez 63s for reconnaissance,
but it is not certain that these machines are used for
artillery spotting. At the moment the aircraft used by the
world's air forces for this latter duty are mainly single-
engined two-seaters. The high monoplane wing is favoured
as good visibility is essential and the machines are of
robust construction.
The Lysander obtains its slow-flying qualities from
Handley Page lift slots and slotted flaps which enable the
machine to be flown even in a careless manner yet with
complete safety. Take-off and landing qualities are, of
course, also improved.
Although the majority of artillery observation machines
are of high-wing design the standard type in use in the
U.S. Army Air Corps—the North American O-47—is a mid-
wing monoplane carrying a crew of three and having
accommodation for an observer in the bottom of the fuse-
lage, which is provided with appropriate transparent
panels.
More lately the Bristol Company has built the type 148
army co-operation machine, which is arranged as a low-
wing monoplane. The crew has a roomy transparent cock-
pit enclosure.
Above is the Fieseler Storch,
a slow-flying machine used
by Germany for army co-
operation work.
A distinctive twin-engined
army co-operation machineis the Focke Wulf Fw 189
shown on the left.
Some time ago the
French developed what
seemed to amount to a
passion for what they
called the avion de travaille, which could be used as an
army co-operation machine or advanced trainer. Typically
this type was a twin-engined monoplane of very sturdy
and simple construction, special consideration being given
to the view of the observer. The external transparent
observation " cars " seem to have been abandoned.
The best example of the light army co-operation machine
at present in service is Germany's Fieseler Storch, which
can fly at about 31 m.p.h. It has a 240 h.p. engine, but
top speed has been sacrificed to usefulness at the lower end
of the speed range and to vision, the cabin having side
windows built out from the fuselage proper.
Of similar layout is the Stinson "liaison observation"
machine now being built for the U.S. Army Air Corps.
Slots and flaps are fitted and visibility from the cabin is
unusually good, but performance details are lacking.
Although rotating-wing aircraft are often condemned lor
army co-operation duties on account of the vulnerability
and complicated maintenance, various types have been
considered for the work. These are the Cierva (hinged
blade with tilting-axis control); the Hafner (hinged blade
with feathering control) ; the Herrick (rigid rocking blade
with rotor control); and the Wilford (semi-rigid blade with
feathering control). The possibilities of helicopters have
not been overlooked ; these might have a single rotor, co-
axial rotors or side-by-side rotors.
With regard to equipment, one of the most promising
developments is television, which is generally considered
to have great possibilities for reconnaissance work.
Designation of
Aircraft
„ GREAT BRITAIN
Westland Lysander
FRANCE
Hanriot 510
AMERICA
North American 0.47
_. GERMANY
R«eler Storch
HenschelHs 126
BOHEMIA-MORAVIAAwoA-304...
LetovS-50 ."
r ITALYUproniCo 134 .
Kr;n,<KjRo37
1AR. ^"MANIA
Span
ft. in.
50 0
49 3
46 4
46 9
47 7
62 II
56 0
44 2
31 235 4
40 ?
W.ng
Area
«i. ft
260
339
348.6
279.7
340
489.6
462
290.5
337.4
385
ARMY CO-OPERATION
Wing
Load-
ing
Ib./
sq. It.
23.1
24.19
21.6
9.8
20.8
19.63
17.9
19.6
15.4
17.5
GrossWeicht
IV,
6,015
8,184
7.533
2.910
7,084
°,58I
8,291
5,334
5.214
6,760
Disposabl
e
Loa
d
Ib.
1,855
2,118
1.698
1.014
2 332
2.981
1.481
2,204
1.837
1.950
Engine Type
Bristol Perseus XII
Gnome-Rhone K9
Wright Cyclone GI03A ...
Argus As 10c
Bramo Fafnir 323
Walter Super-Castor 1-MR
Avia RK. 17
Gnome-Rhone 14M
Isotta-Fraschini XI RC.40
Pi»B<rioPXR
I.A.R. K.I4
#B
A
A
A
A
A
A
A
A
L
A
A
AIRCRAFT
RatedPower
h.p.
745
1.540
860
240
830
860
840
870
900
700
870
Max. At.
Speed rained
at
m.p.h. ft.
230 10.000
217 9,800
243 -
108 —
229 16.400
200 5,740
187 3,280
223 11,480
242 —
201 9.800
208 12,150
Climb
To In
ft. min.
15,000 11.5
9,800 6
10,000 5.75
3,280 4
19.680 11.7
13,120 19
16,400 16
11.400 5.5
19.680 16
13.100 8.5
ServiceCeiling
tt
26.000
22,960
29,700
17,000
26.400
19 000
24.600
27.800
24,000
23,000
26,200
TypicalArmament
3 rang
3 rang
2 remg
None
2 rcme
3 remg
3 remg
3 rcmij
3 rang3 rang
Z rents
Progres
s
IS
PA
IS
IS
IS
PA
PA
OP
PA
OP
OP